KR20170030852A - Grinding method - Google Patents

Abstract

The purpose of the present invention is to reduce grinding time. A grinding method comprises: a preliminary grinding process of grinding a plate-shaped workpiece (W) by a finishing grinding means (80) just before reaching a finishing thickness; a thickness measurement process of measuring the thickness of the plate-shaped workpiece after the preliminary grinding; a calculation process of calculating change of a distance between a retaining surface (42) of a chuck table before and after inclination adjustment of the chuck table (41) and a grinding surface (83a) of a finishing grinding stone (83) from the measured thickness of the plate-shaped workpiece; and a height adjustment process of adjusting the inclination of the chuck table while adjusting the height of the finishing grinding means such that the relative movement speed between the finishing grinding stone and the plate-shaped workpiece is zero in a state where the grinding surface is in contact with the upper surface of the plate-shaped workpiece on the basis of the change.

Description

GRINDING METHOD

The present invention relates to a grinding method for grinding a plate-like workpiece to a desired thickness while measuring the thickness thereof.

In a grinding process, a grinding process is performed while measuring the thickness of a plate-like work with a contact type height gauge (see, for example, Patent Document 1). In the contact type height gauge, the pair of contacts are brought into contact with the upper surface of the plate-shaped workpiece and the upper surface of the chuck table, and the thickness of the plate-like workpiece is detected from the difference in height of the contact position. In addition, as a grinding method for a bonded work comprising a plurality of plate-shaped workpieces, there is known a method of grinding while measuring the thickness of the upper workpiece of the grinding target by non-contact type thickness measuring means (see, for example, Patent Document 2). In the non-contact type thickness measuring means, the thickness of the plate-shaped workpiece is detected from the optical path difference of the laser light reflected by the upper and lower surfaces of the upper workpiece.

It is also known to combine a contact type height gauge and non-contact type thickness measuring means to grind while measuring the thickness of a plate-like work (see, for example, Patent Document 3). In this grinding method, the roughing amount is adjusted while measuring the total thickness of the plate-like work including the thickness of the protective tape with a contact-type height gauge at the time of roughing. Then, during finishing grinding, the finishing amount is controlled while only the thickness of the plate-like workpiece is measured by the non-contact type thickness measuring means. In addition to the grinding method described above, there is also known a method of grinding the plate-shaped workpiece to an even thickness by adjusting the inclination of the chuck table relative to the grinding means based on the measured thickness of the plate-like workpiece (see, for example, Patent Document 4 ).

[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2008-073785 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-264913 [Patent Document 3] Japanese Patent Laid-Open No. 2007-335458 [Patent Document 4] JP-A-2013-119123

In the grinding method described in Patent Document 4, in order to adjust the inclination of the chuck table, the thickness of a predetermined portion of the plate-like workpiece is measured while the grinding means is retracted (raised) from the chuck table. Then, the inclination of the chuck table is adjusted based on the measurement result. Therefore, there is a problem that the moving distance of the grinding means to the grinding start position becomes long, and the grinding process takes time.

When the thickness of the plate-shaped workpiece is not measured, the height of the top surface of the chuck table is measured with the grinding stone retracted from the chuck table, and then the inclination of the chuck table is adjusted. Then, the height of the top surface of the chuck table is measured again, and the amount of grinding feed is calculated based on the difference in height of the top surface before and after the tilt adjustment. As described above, since the measurement is carried out two times before and after the tilt adjustment, it takes time to calculate the grinding feed amount. Therefore, in addition to an increase in the moving distance of the grinding means, grinding processing has also taken time.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a grinding method capable of shortening a grinding time.

The grinding method of the present invention is a grinding method comprising grinding means for grinding a grinding surface of a grinding wheel by abutting a grinding surface of a grinding stone on an upper surface of a plate work held by a chuck table, Grinding means for grinding the workpiece in the grinding and conveying direction; grinding means for grinding the grinding means in the grinding and conveying direction; grinding means for grinding the grinding means; grinding means for grinding the grinding means; And a tilting adjustment means for adjusting a tilting relationship between the grinding means and the grinding means. The grinding method includes grinding the grinding means to grind the plate-like workpiece with a thickness not reaching a predetermined finishing thickness, , The measuring means is moved in the radial direction by the radial moving means to the plate-shaped work ground in the preliminary grinding step A thickness measuring step of measuring a thickness in a radial direction of the chuck table and a tilt adjusting means for adjusting a thickness relationship between the chuck table and the grinding means by the tilt adjusting means so that the finish thickness in the radial direction becomes uniform, Calculating a change amount of a distance between the upper surface of the chuck table and the grinding surface of the grinding stone when the grinding wheel is adjusted; and a grinding and grinding device that operates the grinding transfer means and the tilt adjusting means together based on the amount of change calculated in the calculating step, A height adjustment step of maintaining the grinding surface in contact with the ground surface of the workpiece in the preliminary grinding step during the tilt adjustment operation by the adjustment means; The grinding means is grinded and transferred by the grinding and conveying means while measuring the thickness of the work, It includes a finish grinding process.

According to this configuration, the grinding surface of the grinding stone at a predetermined height with respect to the chuck table is transferred to the plate-shaped work by the preliminary grinding step. Therefore, by measuring the thickness of the plate-like work, the distance between the upper surface of the chuck table and the grinding surface of the grinding stone is indirectly determined. Further, from the measurement result of the thickness of the plate-like work, the amount of change in the distance between the upper surface of the chuck table and the grinding surface of the grinding wheel when the inclination of the chuck table is adjusted is calculated. The grinding means and the tilt adjusting means are operated together so that the contact state between the surface to be ground and the ground surface of the plate-shaped workpiece is maintained based on the amount of change. Therefore, the height of the grinding means is adjusted following the tilt adjusting operation of the chuck table. Therefore, the moving distance of the grinding means at the time of adjusting the inclination can be minimized, and the grinding time can be shortened.

The grinding method of the present invention is a grinding method comprising grinding means for grinding a grinding surface of a grinding wheel by abutting a grinding surface of a grinding stone on an upper surface of a plate work held by a chuck table, Grinding means for grinding the workpiece in the grinding and conveying direction; grinding means for grinding the grinding means in the grinding and conveying direction; grinding means for grinding the grinding means; grinding means for grinding the grinding means; And a tilting adjustment means for adjusting a tilting relationship between the grinding means and the grinding means. The grinding method includes grinding the grinding means to grind the plate-like workpiece with a thickness not reaching a predetermined finishing thickness, , The measuring means is moved in the radial direction by the radial moving means to the plate-shaped work ground in the preliminary grinding step A thickness measuring step of measuring a thickness in a radial direction of the chuck table and a tilt adjusting means for adjusting a thickness relationship between the chuck table and the grinding means by the tilt adjusting means so that the finish thickness in the radial direction becomes uniform, Calculating a change amount of a distance between the upper surface of the chuck table and the grinding surface of the grinding stone when the grinding wheel is adjusted; A height adjusting step of maintaining the grinding feed rate of the grinding means by the feeding means; and a grinding step of grinding the grinding means by grinding and conveying means while measuring the thickness of the plate- And a finish grinding process for grinding the plate-like work.

According to this configuration, the grinding surface of the grinding stone at a predetermined height with respect to the chuck table is transferred to the plate-shaped work by the preliminary grinding step. Therefore, by measuring the thickness of the plate-like work, the distance between the upper surface of the chuck table and the grinding surface of the grinding stone is indirectly determined. Further, from the measurement result of the thickness of the plate-like work, the amount of change in the distance between the upper surface of the chuck table and the grinding surface of the grinding wheel when the inclination of the chuck table is adjusted is calculated. The grinding means and the tilt adjusting means are operated together so that the relative moving speed between the grinding stone and the plate-shaped work becomes the grinding feed speed, based on the amount of change. That is, the inclination of the chuck table is adjusted while grinding the planar work. Therefore, the slope adjusting time can be effectively utilized, and the grinding time can be shortened.

According to the present invention, it is possible to shorten the grinding time by minimizing the amount of movement of the grinding means.

1 is a perspective view of a grinding apparatus according to the present embodiment.
Fig. 2 is a schematic view of the grinding apparatus according to the embodiment around the finishing grinding position.
3A to 3D are explanatory diagrams of a first operation pattern of the grinding method according to the present embodiment.
4A to 4D are explanatory diagrams of a second operation pattern of the grinding method according to the present embodiment.
5A to 5D are explanatory diagrams of a third operation pattern of the grinding method according to the present embodiment.

Hereinafter, a grinding apparatus will be described with reference to the accompanying drawings. 1 is a perspective view of a grinding apparatus according to the present embodiment. On the other hand, the present embodiment is not limited to the configuration shown in Fig. The grinding apparatus may be configured as long as the grinding process can be applied to the plate-like work.

As shown in Fig. 1, the grinding apparatus 1 is a fully automatic type machining apparatus, and is a series of operations including a carry-in process, a roughing process, a finish grinding process, a cleaning process, and a carry- Is fully automatic. The plate-like workpiece W is formed in a substantially disk shape, and is made of, for example, a semiconductor substrate such as silicon or gallium arsenide, an inorganic material substrate such as ceramic, glass, or sapphire, or a package substrate of a semiconductor product.

On the front side of the base 10 of the grinding apparatus 1, a pair of cassettes 13 accommodating a plurality of plate-shaped workpieces W are disposed. A cassette robot 15 for loading and unloading the plate-like work W with respect to the cassette 13 is provided at the rear of the pair of cassettes 13. A positioning mechanism 20 for positioning the plate-like workpiece W before grinding and a cleaning mechanism 25 for cleaning the grinded plate-like workpiece W are provided on both sides of the cassette robot 15 at an oblique angle . Between the positioning mechanism 20 and the cleaning mechanism 25 there are provided a carrying means 30 for carrying the plate-like workpiece W before grinding into the chuck table 41, W) is carried out.

The cassette robot 15 is constituted by a hand portion 17 provided at the tip of a robot arm 16 composed of a multi-joint link. The cassette robot 15 carries the plate-like workpiece W before grinding from the cassette 13 to the positioning mechanism 20, and the plate-like workpiece W from the cleaning mechanism 25 to the cassette 13 W are transported. The positioning mechanism 20 is constituted by disposing a plurality of positioning pins 22 which are movable forward and backward relative to the center of the temporary placement table 21 around the temporary placement table 21. [ In the positioning mechanism 20, a plurality of positioning pins 22 are struck against the outer circumferential edge of the plate-like work W arranged on the temporary placement table 21 so that the center of the plate- (21).

The carrying means 30 is constituted by providing a carrying pad 32 at the tip of the carrying arm 31 which can be pivotable on the base 10. In the carrying means 30, the plate-like work W is lifted from the provisional arrangement table 21 by the carry-in pad 32 and the carry-in pad 32 is turned by the carry-in arm 31, The planar work W is carried. The carry-out means 35 is constituted by providing a carry-out pad 37 at the tip of the carry-out arm 36 which can be pivotable on the base 10. The carrying-out means 35 lifts the plate-like work W from the chuck table 41 by the carrying-out pad 37 and turns the carrying-out pad 37 by the carrying-out arm 36, The plate-like work W is carried out.

The cleaning mechanism 25 includes various nozzles (not shown) for spraying cleaning water and drying air toward a spinner table (not shown). In the cleaning mechanism 25, the spinner table holding the plate-like work W is lowered into the base 10, the washing water is sprayed in the base 10, the plate-like workpiece W is spinner-cleaned, And the plate-like work W is dried by spraying. A turntable 40 having three chuck tables 41 arranged at equal intervals in the circumferential direction is provided behind the loading means 30 and the carrying means 35. [

On the upper surface of the chuck table 41, a holding surface 42 (see Fig. 2) is formed by a porous ceramic material. The holding surface 42 is formed in a conical shape with a slightly lower outer periphery at the center of rotation of the chuck table 41 (see FIG. 2). When the plate-like workpiece W is attracted and held on the holding surface 42, the plate-like workpiece W also becomes a conical shape with a gentle slope along the holding surface 42. In the chuck table 41, the inclination of the roughing means 60 and the finishing grinding means 80 is adjusted by the inclination adjusting means 43 (see Fig. 2). The inclination adjusting means 43 will be described later.

The turntable 40 intermittently rotates at intervals of 120 degrees so that the carry-in / carry-out position at which the plate-shaped workpiece W is carried in and out, the roughing position in place of the roughing means 60, As shown in FIG. In the roughing position, the planar workpiece W on the chuck table 41 is roughly ground to a predetermined thickness by the roughing means 60. In the finish grinding position, the plate-like work W on the chuck table 41 is finely grinded to the finished thickness by the finishing grinding means 80. A column 11 supporting the roughing means 60 and a column 12 supporting the finish grinding means 80 are provided in the vicinity of the roughing position and the finish grinding position.

The front surface of the column 11 is provided with grinding and conveying means 50 for grinding and conveying the grinding means 60 in the grinding and conveying direction while approaching and separating the grinding means 60 from the chuck table 41. The grinding and conveying means 50 includes a pair of guide rails 51 (only one shown) parallel to the Z axis direction disposed on the front surface of the column 11, And the shaft table 52 is slidably mounted. On the front surface of the Z-axis table 52, the roughing means 60 is supported through the housing 53. A ball screw 54 is screwed on the back side of the Z-axis table 52 and a drive motor 55 is connected to one end of the ball screw 54. The ball screw 54 is rotationally driven by the drive motor 55 so that the roughing means 60 is moved along the guide rail 51 in the Z axis direction.

The front surface of the column 12 is provided with a grinding and conveying means 70 for grinding and conveying the finishing grinding means 80 in the grinding conveying direction while approaching and separating the chuck table 41. The grinding and conveying means 70 includes a pair of guide rails 71 (only one shown) parallel to the Z axis direction disposed on the front surface of the column 12, And a shaft table (not shown) is slidably provided. On the front surface of the Z-axis table, a finishing grinding means 80 is supported through a housing 73. A ball screw 74 is screwed on the back side of the Z axis table, and a drive motor 75 is connected to one end of the ball screw 74. The ball screw 74 is rotationally driven by the drive motor 75 so that the finishing grinding means 80 is moved along the guide rail 71 in the Z axis direction.

The roughing means 60 and the finishing grinding means 80 are constituted by mounting mounts 62 and 82 at the lower end of a cylindrical spindle. On the lower surface of the mount 62 of the roughing means 60, a grinding wheel 64 for roughing in which a plurality of rough grinding stones 63 are annularly arranged is mounted. The roughing grindstone 63 is made of, for example, a diamond grindstone hardened with a bonding agent such as a metal bond or a resin bond. A grinding wheel 84 having a plurality of finishing grindstones 83 arranged in an annular shape is mounted on the lower surface of the mount 82 of the finishing grinding means 80. The finishing grinding stone 83 is formed as an abrasive grain having a particle diameter smaller than that of the rough grinding stone 63. [

In the roughing position, a contact-type top surface height measuring means 85 is provided adjacent to the roughing means 60 to measure the height of the top surface of the workpiece W. The upper surface height measuring means 85 is a contact height gauge and contacts the upper surface of the plate-shaped workpiece W and detects the height of the upper surface of the workpiece W from the height of the contact position. The non-contact type thickness measuring means 88 for measuring the thickness of the plate-like work W is provided adjacent to the finish grinding means 80 at the finish grinding position. The thickness measuring means 88 irradiates the plate-shaped workpiece W with laser light and measures the thickness of the plate-like workpiece W from the optical path difference of the laser light reflected by the upper and lower surfaces of the plate-

In the base 10, there is provided a control means 90 for controlling the respective parts of the grinding apparatus 1 as a whole. The control means 90 controls the roughing control by the roughing means 60, the finishing grinding control by the finishing grinding means 80, the thickness measurement control of the plate work W and the chuck table 41, and the like. On the other hand, the control means 90 is constituted by a processor for executing various processes, a memory and the like. The memory is composed of one or a plurality of storage media such as a ROM (Read Only Memory) and a RAM (Random Access Memory) depending on the purpose. In the memory, the roughing amount, the thickness measurement result of the plate-like workpiece W, the finish thickness of the target plate-like workpiece W, the tilt adjustment amount of the chuck table 41, and the like are temporarily stored.

In this grinding apparatus 1, the plate-shaped workpiece W is conveyed from the cassette 13 to the positioning mechanism 20, and the plate-like workpiece W is centered by the positioning mechanism 20. Next, the plate-shaped workpiece W is carried on the chuck table 41, and the plate-like workpiece W is positioned at the roughing position and the finish grinding position by the rotation of the turntable 40. [ In the roughing position, roughing is performed while the height of the upper surface of the plate-like work W is measured by the upper surface height measuring means 85, and the plate-like work W is subjected to the roughing means 60 until the predetermined amount of roughing is reached. . In the finish grinding position, the plate-like work W is preliminarily ground to a thickness not reaching the finish thickness, and then the thickness of the plate-like work W is measured at a plurality of positions. The inclination of the chuck table 41 is finely adjusted while the finishing grinding means 80 and the inclination adjusting means 43 are operated together based on the measurement result of the thickness. After the inclination adjustment, the plate-shaped workpiece W is ground to the finished thickness, and the plate-like workpiece W is formed to have an equal thickness.

Hereinafter, the structure of the grinding means and the chuck table according to the present embodiment will be described with reference to Fig. Fig. 2 is a schematic view of the grinding apparatus according to the embodiment around the finishing grinding position. On the other hand, Fig. 2 shows a state in which the plate-shaped workpiece after completion of roughing is positioned at the finish grinding position.

2, the chuck table 41 is rotatably mounted on the turntable 40 via the tilt adjusting means 43. The chuck table 41 is rotatably mounted on the turntable 40 via the tilt adjusting means 43. [ The inclination adjustment means 43 is composed of two movable columns 43a (only one shown) and one fixed column 43b, and supports the periphery of the chuck table 41 at three points. The movable column 43a is constituted by, for example, an electric actuator. In the inclination adjustment means 43, the chuck table 41 is inclined with the fixed column 43b as a fulcrum by the upward and downward movement of the two movable columns 43a. The two movable columns 43a are operated so that the grinding surface 83a of the finishing grinding stone 83 and the holding surface 42 of the chuck table 41 are parallel to each other at the time of finish grinding, (41) is adjusted. Finishing grinding means (80) is provided above the turntable (40). The chuck table 41 is positioned such that the grinding wheel 83 passes the center of the plate-like work W. The finishing grinding means 80 reduces the thickness of the plate-like work W by contacting the grinding surface 83a of the grinding stone 83 to the upper surface of the plate-like work W held by the chuck table 41. [

A thickness measuring means 88 for measuring the thickness of the plate-like work W is provided on the side of the finishing and grinding means 80. The thickness measuring means 88 is provided at the tip of a swivel arm 89 which can pivot around a predetermined portion of the outer periphery of the turntable 40 as a fulcrum. The swivel arm 89 constitutes a radial direction moving means in the claims and the thickness measuring means 88 is moved in the radial direction on the plate-like work W by the swiveling of the swivel arm 89. The thickness measuring means 88 irradiates the plate-like workpiece W with laser light and calculates the thickness of the plate-like workpiece W based on the optical path difference of the laser light reflected on the upper and lower surfaces of the plate-like workpiece W . The thickness measurement is carried out at any three points in the vicinity of the center of the chuck table 41, near the outer periphery of the chuck table 41, and between the center and the outer periphery. On the other hand, in the present embodiment, the configuration in which the thickness of the plate-shaped workpiece W is measured at three sites is described, but the present invention is not limited to this configuration. The measurement site may be measured at several sites if the site is at least two sites.

The thickness measuring means 88, the grinding and conveying means 70 and the inclination adjusting means 43 are connected to the control means 90. The thickness of the planar workpiece W measured by the thickness measuring means 88 is output to the control means 90. [ The control means 90 controls the chuck table 41 and the finishing grinding means 80 so that the chuck table 41 and the finishing grinding means 80 can be adjusted in accordance with the measured thickness of the chuck table 41, 42 and the grinding surface 83a of the finishing grinding stone 83 is calculated. That is, the inclined state of the chuck table 41 is recognized from three measurement points in the radial direction.

The control means 90 controls the drive amount of the movable column 43a of the tilt adjusting means 43 and the feed amount of the grinding and conveying means 70 at the time of the tilt adjustment based on the change amount. After the inclination adjustment, the control means 90 controls the thickness of the plate-shaped workpiece W by the thickness measuring means 88 while monitoring the thickness of the plate-like workpiece W until the finish thickness of the plate- 70). On the other hand, the finishing thickness of the plate-like workpiece W to be set in advance is stored in the memory of the control means 90. [

Next, a grinding method performed in the first operation pattern will be described. 3A to 3D are explanatory diagrams of a first operation pattern of the grinding method according to the present embodiment. 4A to 4D are explanatory diagrams of a second operation pattern of the grinding method according to the present embodiment.

As shown in Figs. 3A to 3D, in the grinding method according to the present embodiment, the preliminary grinding step, the thickness measuring step, the calculating step, the height adjusting step, and the finishing grinding step are performed in this order . On the other hand, the grinding feed rate of the finishing grinding means 80 at the finish grinding position is relatively slow compared with the grinding feed rate of the roughing means 60 (see Fig. 1) at the roughing position. Thus, in the grinding method according to the present embodiment, it is possible to reduce the time required for the entire grinding process by shortening the operating time at the finish grinding position as much as possible.

Before the plate-shaped workpiece W is located at the finish grinding position, the roughing step is first performed at the roughing position (see Fig. 1). In the roughing step, roughing is performed while measuring the height of the top surface of the plate-shaped workpiece W, and the plate-like workpiece W is ground until it reaches the target roughing amount. On the other hand, in the roughing step, the inclination of the chuck table 41 is adjusted so that the grinding surface of the roughing means 60 and the holding surface 42 of the chuck table 41 become parallel. However, the degree of parallelism between the grinding surface of the roughing means 60 and the holding surface 42 of the chuck table 41 includes an error. Therefore, the plate-like workpiece W immediately after the roughing has a non-uniform thickness distribution. In the first operation pattern, the plate-like work W in which the central portion is thinned by the roughing process and the outer peripheral portion is formed thick is described.

When the roughing process is completed, the plate-shaped workpiece W is positioned at the finishing grinding position from the roughing position by the intermittent rotation of the turntable 40. At this time, the chuck table 41 is positioned at the finish grinding position while maintaining the inclination at the time of roughing. However, in the roughing means 60 and the finishing grinding means 80, the contact angle of the grinding surface with the plate-like work W may be slightly different due to an attachment error or the like. Thus, in the grinding method according to the present embodiment, at the finishing grinding position, first, the preliminary grinding step by the finishing grinding means 80 is performed.

As shown in Fig. 3A, in the preliminary grinding step, the finish grinding means 80 grinds the plate-like work W to a thickness that does not reach a preset final thickness. More specifically, the finishing grinding means 80 is lowered while being rotated, and the grinding surface 83a of the finishing grinding stone 83 and the upper surface of the plate-like work W are in rotational contact with each other, whereby the plate-like work W is preliminarily ground . Then, at a time point when the predetermined grinding amount is reached, the feeding operation of the grinding and moving means is stopped. At this time, the grinding surface 83a is in contact with the upper surface of the plate-like work W. On the other hand, at this time, the rotation operation of the finishing grinding means 80 may be stopped.

In the preliminary grinding step, since the upper surface of the plate-shaped workpiece W is slightly ground, the upper surface of the plate-like workpiece W is smoothed. Therefore, in the next thickness measuring process, it is possible to prevent the measurement light emitted from the thickness measuring means 88 from being irregularly reflected on the upper surface of the plate-like work W. As a result, the influence on the thickness measurement of the plate-shaped workpiece W can be minimized. The surface shape of the grinding surface 83a of the finishing grinding stone 83 is transferred to the plate-like work W so that the grinding surface 83a and the upper surface of the plate-like work W coincide with each other. The thickness of the plate-like work W can be regarded as the distance between the grinding surface 83a of the finishing grindstone 83 and the holding surface 42 of the chuck table 41. [

Next, a thickness measuring process is performed. 3B, in the thickness measuring step, after the grinding feed of the finishing grinding means 80 is once stopped, the thickness measuring means 88 is moved in the radial direction . Thus, the thickness of the plate-shaped workpiece W is measured. More specifically, the swivel arm 89 (radial moving means) is turned to move the thickness measuring means 88 from the center of the plate-like work W toward the outer periphery. At this time, the thickness measuring means 88 measures the thickness of the plate-shaped workpiece W at any three positions in the radial direction of the plate-like workpiece W.

Next, the calculation step is carried out. In the calculating step, the amount of change in the distance between the holding surface 42 and the grinding surface 83a before and after the tilt adjustment is calculated based on the measurement result measured in the thickness measuring process. Since the distance between the holding surface 42 and the grinding surface 83a is different in each of the three measured portions, the inclination state of the chuck table 41 can be recognized from the measurement result. The amount of change in the distance between the holding surface 42 and the grinding surface 83a required for the holding surface 42 and the grinding surface 83a to become parallel to each other can be calculated from the inclined state. That is, the amount of change in the distance between the holding surface 42 and the grinding surface 83a necessary for finishing the plate-shaped workpiece W to an even thickness can be calculated from the thickness measurement result of the plate-like workpiece W.

Next, a height adjustment process is performed. 3C, in the height adjusting step, the grinding and conveying means 70 and the inclination adjusting means 43 (refer to FIG. 3) are provided on the basis of the amount of change in the distance between the holding surface 42 and the grinding surface 83a calculated in the calculating step. ) Are operated together. At this time, the rotation of the finishing grinding means 80 and the chuck table 41 may be stopped. In the state shown in Fig. 3C, since the outer periphery of the work W is thicker than the center of the plate-like work W, the movable column 43a of the tilt adjusting means 43 is raised so as to increase the grinding amount of the outer peripheral portion. As the movable column 43a rises, the finishing grinding means 80 is lifted by an amount corresponding to the rise of the holding surface 42 of the chuck table 41. [ For example, the distance at which the outer periphery Wa of the upper surface of the plate-like work W rises in accordance with the amount of rise of the movable column 43a becomes a distance at which the finishing grinding means 80 ascends.

At this time, the finishing grinding means 80 follows the operation of the movable column 43a and is raised at the same speed as the rising speed of the movable column 43a. For example, the speed at which the outer periphery Wa of the upper surface of the plate-like work W rises in accordance with the ascending speed at which the movable column 43a ascends becomes the speed at which the finishing grinding means 80 ascends. That is to say, the moving speed of the finishing grinding means 80 (the feeding speed) and the moving speed of the movable column 43a of the inclination adjusting means 43 are adjusted so that the relative moving speed between the finishing grinding wheel 83 and the plate- The moving speed is controlled. Thereby, during the tilt adjustment operation, the state in which the grinding surface 83a is in contact with the upper surface (the surface to be ground) of the plate-like work W is maintained. Therefore, the movement amount of the finishing grinding means 80 at the time of the tilt adjustment can be minimized, and the time required for the tilt adjustment can be shortened. The inclination of the chuck table 41 is adjusted so that the grinding surface 83a and the holding surface 42 are parallel to each other and the finish thickness of the plate-like work W becomes uniform as a result of the tilt adjusting means 43 being driven.

Next, a finish grinding process is performed. As shown in Fig. 3D, in the finishing grinding step, the plate-shaped work W is ground until a predetermined finishing thickness is reached. The finishing grinding means 80 is ground and conveyed by the grinding and conveying means 70 while the finishing grinding means 80 and the chuck table 41 are rotated. The finish grinding is performed while measuring the thickness of the plate-like work W by the thickness measuring means 88 positioned above the outer peripheral edge of the plate-like work W. Then, the grinding feed is stopped when the measured value reaches the set finish thickness, and the finish grinding is ended. As a result, the plate-shaped workpiece W is ground to an even thickness.

Next, the second operation pattern will be described with reference to Figs. 4A to 4D. In the second operation pattern, the shape of the plate-like work after roughing is different from the first operation pattern. On the other hand, in the second operation pattern, a plate-like work having a thick central portion and a thin outer peripheral portion by the roughing process will be described.

As shown in Fig. 4A, first, in the finishing grinding position, a preliminary grinding process is performed, and the plate-shaped workpiece W is ground with a thickness not reaching a predetermined finishing thickness. Then, as shown in Fig. 4B, a thickness measuring process is performed, and the thickness is measured at three portions of the plate-like work W. Next, the calculation process is performed to calculate the grinding surface 83a of the finishing grinding stone 83 and the holding surface 42 of the chuck table 41 before and after the tilt adjustment based on the measurement result measured in the thickness measurement process. Is calculated.

Next, a height adjustment process is performed. 4C, in the height adjusting step, the grinding and conveying means 70 and the inclination adjusting means 43 (see FIG. 4) are controlled based on the amount of change in the distance between the holding surface 42 and the grinding surface 83a calculated in the calculating step. ) Are operated together. 4C, the movable column 43a of the tilt adjusting means 43 is formed so as to increase the amount of grinding at the central portion because the outer periphery of the plate-like work W is thinner, as described above, . The finishing grinding means 80 is lowered by the descent of the holding surface 42 of the chuck table 41 as the movable column 43a descends. For example, the distance at which the center Wb of the upper surface of the plate-shaped work W descends depends on the amount of descent of the movable column 43a, which is the distance at which the finishing grinding means 80 descends.

At this time, the finish grinding means 80 follows the operation of the movable column 43a and descends (grinds and feeds) at the same speed as the descending speed of the movable column 43a. For example, the speed at which the center Wb of the upper surface of the plate-like work W descends in accordance with the lowering speed at which the movable column 43a descends becomes the lowering speed of the finishing grinding means 80. That is to say, the moving speed of the finishing grinding means 80 (the feeding speed) and the moving speed of the movable column 43a of the inclination adjusting means 43 are adjusted so that the relative moving speed between the finishing grinding wheel 83 and the plate- The moving speed is controlled. Thus, during the tilt adjustment operation, the grinding surface 83a is held in contact with the upper surface (the surface to be ground) of the plate-like work W near the center thereof. Therefore, the movement amount of the finishing grinding means 80 at the time of the tilt adjustment can be minimized, and the time required for the tilt adjustment can be shortened. The inclination of the chuck table 41 is adjusted so that the grinding surface 83a and the holding surface 42 are parallel to each other and the finish thickness of the plate-like work W becomes uniform as a result of the tilt adjusting means 43 being driven.

Next, a finish grinding process is performed. As shown in Fig. 4 (d), in the finishing grinding step, the plate-shaped work W is ground until a predetermined finishing thickness is reached. As a result, the plate-shaped workpiece W is ground to an even thickness. As described above, also in the second operation pattern, the time required for the entire grinding process can be shortened by shortening the operation time at the finish grinding position as much as possible.

As described above, according to the first and second operation patterns of the grinding method according to the present embodiment, the grinding surface of the finishing grinding stone 83 at a predetermined height with respect to the chuck table 41 83a are transferred to the plate-shaped workpiece W. Therefore, the distance between the holding surface 42 and the grinding surface 83a is determined by measuring the thickness of the plate-like work W. The amount of change in the distance between the holding surface 42 and the grinding surface 83a when the inclination of the chuck table 41 is adjusted is calculated from the thickness measurement result of the plate-like work W. The finishing grinding means 80 and the inclination adjusting means 88 are operated together so that the contact state between the upper surface (the surface to be ground) of the workpiece W and the grinding surface 83a is maintained based on the amount of change . Therefore, the height of the finishing grinding means 80 is adjusted in accordance with the tilt adjusting operation of the chuck table 41. Therefore, the moving distance of the finishing grinding means 80 at the time of adjusting the inclination can be minimized, and the grinding time can be shortened.

Next, the third operation pattern of the grinding method according to the present embodiment will be described with reference to Figs. 5A to 5D. The third operation pattern is different from the first operation pattern in that the inclination adjustment is performed while grinding. Hereinafter, mainly different points will be mainly described. On the other hand, in the third operation pattern, a plate-like work having a thin central portion and a large outer peripheral portion by the roughing process is described, but the present invention is not limited to this configuration. As shown in Fig. 4, the present invention is also applicable to a plate-shaped work having a thick central portion and a thin outer peripheral portion.

As shown in Fig. 5A, first, in the finishing grinding position, a preliminary grinding process is performed, and the plate-like workpiece W is ground with a thickness not reaching a predetermined finishing thickness. Then, as shown in Fig. 5B, a thickness measuring process is performed, and the thickness is measured at three portions of the plate-like work W. Next, the calculation process is performed to calculate the grinding surface 83a of the finishing grinding stone 83 and the holding surface 42 of the chuck table 41 before and after the tilt adjustment based on the measurement result measured in the thickness measurement process. Is calculated.

Next, a height adjustment process is performed. 5C, in the height adjusting step, the grinding and conveying means 70 and the inclination adjusting means 43 (see FIG. 5) are controlled based on the amount of change in the distance between the holding surface 42 and the grinding surface 83a calculated in the calculating step. ) Are operated together. At this time, the finishing grinding means 80 and the chuck table 41 are rotating. 5C, the movable column 43a of the tilt adjusting means 43 is formed so as to increase the amount of grinding of the outer peripheral portion because the outer periphery of the plate-shaped work W is thicker, as described above, . On the other hand, the finishing and grinding means 80 is lowered (grinding and conveying) while maintaining a constant feeding speed by the grinding and conveying means 70 while pushing the grinding surface 83a against the plate-like work W. Thereby, it is possible to adjust the inclination of the chuck table 41 while grinding the plate-like work W.

At this time, the feeding speed of the finishing grinding means 80 is adjusted so that the descending speed of the finishing grinding means 80 with respect to the movable column 43a becomes a speed suitable for finishing grinding. That is to say, the moving speed (feed speed) of the finishing grinding means 80 and the moving speed of the slope adjusting means 43 are adjusted so that the relative moving speed between the finishing grinding wheel 83 and the plate- (43a) is controlled. For example, the grinding feed of the finish grinding means 80 is stopped and the outer periphery Wa of the upper surface of the plate-like work W is moved at the same speed as the grinding feed speed in accordance with the rising speed of the movable column 43a of the slope adjusting means 43 The grinding wheel 83 is grinded and transported. Further, the grinding feed of the finishing grinding means 80 may not be stopped. In this case, the rising speed at which the movable column 43a is lifted is made higher than the feeding speed of the finishing grinding means 80 so that the relative moving speed between the finishing grinding stone 83 and the plate-like work W is equal to the grinding feeding speed .

As described above, since the grinding is performed even during the inclination adjustment, the time for the inclination adjustment can be effectively utilized. Further, it is not necessary to raise the finishing grinding means 80 for adjusting the inclination, and the amount of movement can be minimized. Therefore, the time required for the tilt adjustment can be shortened. The inclination of the chuck table 41 is adjusted so that the grinding surface 83a and the holding surface 42 are parallel to each other and the finish thickness of the plate-like work W becomes uniform as a result of the tilt adjusting means 43 being driven.

After the tilt adjustment, the grinding and feeding continues as it is, and the process proceeds to the finish grinding step. As shown in Fig. 5D, in the finishing grinding step, the plate-shaped work W is ground until a predetermined finishing thickness is reached. As a result, the plate-shaped workpiece W is ground to an even thickness. As described above, in the third operation pattern, since the inclination adjustment of the chuck table 41 is performed while grinding the plate-like work W in the height adjustment step, not only the inclination adjustment time is shortened but also the finish in the finish grinding step The grinding time can also be shortened. Therefore, by shortening the operating time of the grinding apparatus 1 (see Fig. 1) at the finish grinding position as much as possible, the time required for the entire grinding process can be shortened.

On the other hand, the present invention is not limited to the above-described embodiment, and various modifications can be made. In the above-described embodiment, the size, shape and the like shown in the accompanying drawings are not limited to this, but can be appropriately changed within the range of the effect of the present invention. In addition, it is possible to appropriately change the present invention without departing from the scope of the present invention.

For example, in the embodiment described above, the thickness measuring means 88 irradiates the plate-shaped workpiece W with a laser beam to measure the thickness of the plate-like workpiece W, but the present invention is not limited to this configuration. The thickness measuring means 88 may be configured as long as the thickness of the plate-shaped workpiece W can be measured.

In the embodiment described above, the three chuck tables 41 are arranged on the turntable 40, but the present invention is not limited to this configuration. The turntable 40 may have a plurality of chuck tables 41 arranged at even intervals in the circumferential direction. For example, two chuck tables 41 may be arranged on the turntable 40, or four or more chuck tables 41 may be arranged.

In the embodiment described above, the inclination adjusting means 43 is composed of the two movable columns 43a and one fixed column 43b, but the present invention is not limited to this configuration. The inclination adjustment means 43 may be composed of three or more movable columns 43a with respect to one fixed column 43b or three or more movable columns 43a alone.

In the above-described embodiment, the grinding apparatus 1 is configured to perform the first, second, and third operation patterns, but the present invention is not limited to this structure. The operation pattern of the grinding apparatus 1 may include the preliminary grinding process, the thickness measuring process, the calculating process, the height adjusting process, and the finishing grinding process.

In the above-described embodiment, the tilt adjustment of the chuck table 41 is performed while the finishing grinding means 80 is grinding and conveyed in the height adjustment step of the third operation pattern. However, the present invention is not limited to this configuration. In the height adjusting step, while the finishing grinding means 80 is rotated, the grinding feed by the grinding and conveying means 70 may be once stopped and the inclination adjustment of the chuck table 41 may be performed. In this case, it is necessary to set the moving speed of the movable column 43a to an appropriate grinding feed rate suitable for finishing grinding.

In the above embodiment, the grinding and conveying means 70 and the tilt adjusting means 43 are operated together based on the amount of change in the distance between the holding surface 42 and the grinding surface 83a. However, . The grinding and conveying means 70 and the tilt adjusting means 43 may be operated together based on the amount of change of the angle formed by the holding surface 42 and the grinding surface 83a.

INDUSTRIAL APPLICABILITY As described above, the present invention has an effect that the grinding time can be shortened, and is particularly useful for a grinding method for grinding a desired thickness while measuring the thickness of a plate-like work.

W: Platework 1: Grinding device
41: chuck table 43: inclination adjusting means
70: grinding and conveying means 80: finishing grinding means (grinding means)
83: Grinding stone 83a: Grinding surface
88: thickness measuring means 89: swivel arm (radial moving means)

Claims (2)

A chuck table for holding a planar workpiece; grinding means for reducing the thickness by bringing the grinding surface of the grinding wheel into contact with the upper surface of the planar workpiece held by the chuck table; And a grinding means for grinding a workpiece to be grinded by grinding means; measuring means for measuring a thickness of the workpiece to be ground by the grinding means; radial moving means for moving the measuring means in a radial direction of the chuck table; And a tilt adjusting means for adjusting a tilt relationship between the grinding means and the grinding means,
A preliminary grinding step of grinding the plate-shaped workpiece to a thickness not reaching a predetermined finishing thickness using the grinding means;
A thickness measuring step of measuring the thickness in the radial direction by moving the measuring means in the radial direction by the radial moving means on the planarized work ground in the preliminary grinding step;
Wherein when the tilt relationship between the chuck table and the grinding means is adjusted by the tilt adjusting means so that the finishing thickness in the radial direction becomes equal based on the measurement result measured in the thickness measuring process, A calculating step of calculating a change amount of a distance between an upper surface and the grinding surface of the grinding stone;
Wherein the grinding and conveying means and the tilt adjusting means are operated together on the basis of the amount of change calculated in the calculating step, and during the tilt adjusting operation by the tilt adjusting means, A height adjusting step of maintaining a state in contact with the grinding surface,
After the height adjusting step, the thickness of the plate-like workpiece is measured by the measuring means up to a finishing thickness set in advance, and the grinding means is grinded and transferred by the grinding / conveying means to finish grinding the plate-
/ RTI > A chuck table for holding a planar workpiece; grinding means for reducing the thickness by bringing the grinding surface of the grinding wheel into contact with the upper surface of the planar workpiece held by the chuck table; And a grinding means for grinding a workpiece to be grinded by grinding means; measuring means for measuring a thickness of the workpiece to be ground by the grinding means; radial moving means for moving the measuring means in a radial direction of the chuck table; And a tilt adjusting means for adjusting a tilt relationship between the grinding means and the grinding means,
A preliminary grinding step of grinding the plate-shaped workpiece to a thickness not reaching a predetermined finishing thickness using the grinding means;
A thickness measuring step of measuring the thickness in the radial direction by moving the measuring means in the radial direction by the radial moving means on the planarized work ground in the preliminary grinding step;
Wherein when the tilt relationship between the chuck table and the grinding means is adjusted by the tilt adjusting means so that the finishing thickness in the radial direction becomes equal based on the measurement result measured in the thickness measuring process, A calculating step of calculating a change amount of a distance between an upper surface and the grinding surface of the grinding stone;
A height adjusting step of operating the grinding and conveying means and the inclination adjusting means together based on the amount of change calculated in the calculating step and maintaining the grinding feed rate of the grinding means by the grinding and conveying means;
After the height adjusting step, the thickness of the plate-like workpiece is measured by the measuring means up to a finishing thickness set in advance, and the grinding means is grinded and transferred by the grinding / conveying means to finish grinding the plate-
/ RTI >

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